Research On Congestion Control Of Media Flow Transmit Based On UDP

With the population of network and the promotion of multimedia technology,streaming media develops very fast,is widely used in Picture phone,Long-distance education and Video conference. Streaming Media plays more and more important role today,became the focus of Internet aplications.But it also brings more and more questions.Congestion control is the one.Because of the characteristic of streaming media tansmitton,such as low delay,smooth transmit sending rate , streaming media always transmits on UDP .When congetion happens,TCP begins congestion control,but UDP is lack of congestion control,as a result to that congestion can not effectively be solved.It makes bard affect to the streaming media's QoS.To solve this question,this paper advances a congestion scheme-MDCC.It is recognized perfect that Router Queue Management mechanism mixes with end-to-end congestion mechanism.On end-to-end congestion mechanism,this paper compare today's TCP-friendly congestion control mechanisms,finds that TFRC is one of the best TCP-friendly congestion control mechanisms suit for streaming media transmitton. Then,during all router congestion mechanisms RED is the famous Active Queue Management mechanism.This paper combines RED with DiffServ to a delay-sensitive adaptive RIO mechanism-DARIO-C.DARIO-C can not only solve the question that parameters of RIO can hardly setted,but also deal with different Qos of different applications.At last integrate it with TFRC to a congestion control mechanism based on UDP-MDCC.This paper studys MDCC,then use emluator NS2 to emluate MDCC.